155 research outputs found
Quench behavior of high temperature superconductor (RE)Ba2Cu3Ox CORC cable
High temperature superconductor (HTS) (RE)Ba2Cu3Ox (REBCO) conductor on round core cable (CORC) shows great advantages on high current capacity and power density. In REBCO CORC cables, current is redistributed among tapes through terminal contact resistances (TCR) when a local quench occurs. Therefore, its quench behaviour is different from single tape situation. To better understand the underlying physical process of local quenches in CORC cables, a new 3D multi-physics modelling tool for CORC cables is developed and presented in this paper. In this model, the REBCO tape is treated as a thin shell without thickness, and four models are coupled: T-formulation model, A-formulation model, a heat transfer model and an equivalent circuit model. The T-formulation is applied to the conductor shell only to calculate current distribution, which will be input into A-formulation model; the A-formulation is applied to the whole 3D domain to calculate magnetic field, which is then fed back to the T-formulation model. The hot spot induced quenches of CORC cables are analysed. The results show that the thermal stability of CORC cable can be considerably improved by reducing TCR. The minimum quench energy (MQE) increases rapidly with the reduction of TCR when the resistance is in a middle range, which is about 5 μΩ ≤ Rt ≤ 200 μΩ in this study. When TCR is too low (Rt 50 μΩ), the MQE shows no obvious variation with TRC. With low TCR, a hot spot in one tape may induce an over-current quench on other tapes. This will not happen in a cable with high TCR. In this case, the tape with hot spot will quench and burn out before inducing a quench on other tapes. The modelling tool developed can be used to design CORC cables with improved thermal stability
Disruption of actin filaments induces mitochondrial Ca2+ release to the cytoplasm and [Ca2+]c changes in Arabidopsis root hairs
<p>Abstract</p> <p>Background</p> <p>Mitochondria are dynamic organelles that move along actin filaments, and serve as calcium stores in plant cells. The positioning and dynamics of mitochondria depend on membrane-cytoskeleton interactions, but it is not clear whether microfilament cytoskeleton has a direct effect on mitochondrial function and Ca<sup>2+ </sup>storage. Therefore, we designed a series of experiments to clarify the effects of actin filaments on mitochondrial Ca<sup>2+ </sup>storage, cytoplasmic Ca<sup>2+ </sup>concentration ([Ca<sup>2+</sup>]<sub>c</sub>), and the interaction between mitochondrial Ca<sup>2+ </sup>and cytoplasmic Ca<sup>2+ </sup>in <it>Arabidopsis </it>root hairs.</p> <p>Results</p> <p>In this study, we found that treatments with latrunculin B (Lat-B) and jasplakinolide (Jas), which depolymerize and polymerize actin filaments respectively, decreased membrane potential and Ca<sup>2+ </sup>stores in the mitochondria of <it>Arabidopsis </it>root hairs. Simultaneously, these treatments induced an instantaneous increase of cytoplasmic Ca<sup>2+</sup>, followed by a continuous decrease. All of these effects were inhibited by pretreatment with cyclosporin A (Cs A), a representative blocker of the mitochondrial permeability transition pore (mPTP). Moreover, we found there was a Ca<sup>2+ </sup>concentration gradient in mitochondria from the tip to the base of the root hair, and this gradient could be disrupted by actin-acting drugs.</p> <p>Conclusions</p> <p>Based on these results, we concluded that the disruption of actin filaments caused by Lat-B or Jas promoted irreversible opening of the mPTP, resulting in mitochondrial Ca<sup>2+ </sup>release into the cytoplasm, and consequent changes in [Ca<sup>2+</sup>]<sub>c</sub>. We suggest that normal polymerization and depolymerization of actin filaments are essential for mitochondrial Ca<sup>2+ </sup>storage in root hairs.</p
Visual Relationship Detection with Relative Location Mining
Visual relationship detection, as a challenging task used to find and
distinguish the interactions between object pairs in one image, has received
much attention recently. In this work, we propose a novel visual relationship
detection framework by deeply mining and utilizing relative location of
object-pair in every stage of the procedure. In both the stages, relative
location information of each object-pair is abstracted and encoded as auxiliary
feature to improve the distinguishing capability of object-pairs proposing and
predicate recognition, respectively; Moreover, one Gated Graph Neural
Network(GGNN) is introduced to mine and measure the relevance of predicates
using relative location. With the location-based GGNN, those non-exclusive
predicates with similar spatial position can be clustered firstly and then be
smoothed with close classification scores, thus the accuracy of top recall
can be increased further. Experiments on two widely used datasets VRD and VG
show that, with the deeply mining and exploiting of relative location
information, our proposed model significantly outperforms the current
state-of-the-art.Comment: Accepted to ACM MM 201
3D-Printed Artificial Microfish
Hydrogel microfish featuring biomimetic structures, locomotive capabilities, and functionalized nanoparticles are engineered using a rapid 3D printing platform: microscale continuous Âoptical printing (μCOP). The 3D-printed Âmicrofish exhibit chemically powered and magnetically guided propulsion, as well as highly efficient detoxification capabilities that highlight the technical versatility of this platform for engineering advanced functional microswimmers for diverse biomedical applications
3D-Printed Artificial Microfish
Hydrogel microfish featuring biomimetic structures, locomotive capabilities, and functionalized nanoparticles are engineered using a rapid 3D printing platform: microscale continuous Âoptical printing (μCOP). The 3D-printed Âmicrofish exhibit chemically powered and magnetically guided propulsion, as well as highly efficient detoxification capabilities that highlight the technical versatility of this platform for engineering advanced functional microswimmers for diverse biomedical applications
The Chinese pine genome and methylome unveil key features of conifer evolution
Conifers dominate the world's forest ecosystems and are the most widely planted tree species. Their giant and complex genomes present great challenges for assembling a complete reference genome for evolutionary and genomic studies. We present a 25.4-Gb chromosome-level assembly of Chinese pine (Pinus tabuliformis) and revealed that its genome size is mostly attributable to huge intergenic regions and long introns with high transposable element (TE) content. Large genes with long introns exhibited higher expressions levels. Despite a lack of recent whole-genome duplication, 91.2% of genes were duplicated through dispersed duplication, and expanded gene families are mainly related to stress responses, which may underpin conifers' adaptation, particularly in cold and/or arid conditions. The reproductive regulation network is distinct compared with angiosperms. Slow removal of TEs with high-level methylation may have contributed to genomic expansion. This study provides insights into conifer evolution and resources for advancing research on conifer adaptation and development
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